For the house I use large flake wood chip. As long as it's kept dry you can put it in deep and if the birds don't turn it over, you can to stop it clagging and it will stay nice for ages, less so in winter. For nest boxes I use a horse bedding product called equinola or something. It's chopped straw, I think with tea tree oil in it. Plain straw is not good as mites can hide inside it. Seems to work well.
Sleeping in nest boxes? I've never found a sensible solution when the nests are in the house where they roost. Some will just do it. I suspect that giving birds roosts from a very early age helps with this, whereas, if they have been sleeping on the floor in their early days, they are likely to continue that idea. You might be able to break the habit by going out after dark and returning them to a roost but in some houses, it's tricky as they can jump back in.
Personally, the answer I have found is to have them lay in a separate house. My birds sleep in one house without nest boxes and I have built simple 'nesters' out of pallets and offcuts where they lay their eggs. Advantages are cleaner eggs as it's easy to move the nester to clean grass. Also if you have broody or a night nester you can go up and pop them back in the house for a few nights which usually breaks the habit as they won't run across a dark field to get back to the nest.
I got this idea when we had a small flock in the garden and they would sleep in the Eglu but lay eggs in the old wooden house we had left there. Eventually we closed off the eglu nest box, took the roosts out of the old house and got nice clean eggs and fewer broodies. So, consider a detached laying 'box' of some sort. Maybe a cheap old house with the roost bars removed.